Best Solar Hot Water System Guides -With Step-by-Step Instructions

DYI-SolarWaterHeatear is an excellent DIY kit meant to teach you how to build your own solar water heater (and not only) at low cost (less than $70). This guide includes over 90 pages of detailed instructions that are very easy to follow. In addition, the kit includes another 11 DIY guides (see below).
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The DIY-HotWater guide is a 70 page manual in PDF format that is going to show you how to build a professional solar hot water system that will reduce your power bill and help the environment.
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Solar Pool Heater its a highly popular project with over 25,000 web and **** sales. Including a 14 pages PDF manual providing plans and step-by-step instructions that will show you how to build your own solar pool heater at low cost (less than $250).

I had a question which is running in my brain for a long time regarding Solar systems.

Generally we see that Sun is a must for Solar to work and most of the times people dont require Hot water during summer, instead they require hot water in winter where power of the Sun is relatively low.

Considering the above factor can u suggest me a best company which provide best efficiency for solar collectors.